We propose to develop and validate tests to assess olfactory function in gene-targeted mice. A simple, rapid and reliable test for odor detection, will be used as a phenotyping assay for both odor detection and odor discrimination in strains of commercially available mice. More sophisticated behavioral measures, including assessing odor detection threshold, odor discrimination, odor memory and, of particular interest, odor quality recognition will also be developed. To facilitate within- and cross-strain comparisons of identified glomeruli, we will construct a metric atlas of the mouse olfactory bulb. All behavior tests will be computer-controlled and yield multiple objective measures of performance. The reliability of the behavioral tests will be established for each wild-type strain and will be defined by intercorrelations of dependent measures and by variance of outcomes among strains. A final report of these studies will incorporate a detailed description of apparatus, methods protocol and files of raw data and summary statistics presented in database and spreadsheet format.